code: def plot_bar_graphs(
      ax, prng, min_value=5, max_value=25, nb_samples=5
  ):
      """Plot two bar graphs side by side, with letters as x-tick labels."""
      x = np.arange(nb_samples)
      ya, yb = prng.randint(min_value, max_value, size=(2, nb_samples))
      width = 0.25
      ax.bar(x, ya, width)
      ax.bar(x + width, yb, width, color="C2")
      ax.set_xticks(x + width, labels=["a", "b", "c", "d", "e"])
      return ax
  
file_path: matplotlib/galleries/examples/style_sheets/style_sheets_reference.py
imports: import matplotlib.pyplot
  import numpy
  import matplotlib.colors
  from matplotlib.patches import Rectangle
label_desc: Use image node_id 3 for calling a global function with example usage: plot_bar_graphs(ax, prng, min_value, max_value, nb_samples) and returns: ax